gcc/testsuite/gcc.dg/20111227-2.c

   1 /* Testcase derived from 20111227-1.c to ensure that REE is combining
   2    redundant zero extends with zero extend to wider mode.  */
   3 /* { dg-do compile  { target i?86-*-* x86_64-*-* } } */
   4 /* { dg-options "-fdump-rtl-ree -O -free" } */
   5
   6 extern void abort (void);
   7
   8 unsigned short s;
   9 unsigned int i;
  10 unsigned long l;
  11 unsigned char v = -1;
  12
  13 void __attribute__((noinline,noclone))
  14 bar (int t)
  15 {
  16   if (t == 2 && s != 0xff)
  17     abort ();
  18   if (t == 1 && i != 0xff)
  19     abort ();
  20   if (t == 0 && l != 0xff)
  21     abort ();
  22 }
  23
  24 void __attribute__((noinline,noclone))
  25 foo (unsigned char *a, int t)
  26 {
  27   unsigned char r = v;
  28
  29   if (t == 2)
  30     s = (unsigned short) r;
  31   else if (t == 1)
  32     i = (unsigned int) r;
  33   else if (t == 0)
  34     l = (unsigned long) r;
  35   bar (t);
  36 }
  37
  38 int main(void)
  39 {
  40   foo (&v, 0);
  41   foo (&v, 1);
  42   foo (&v, 2);
  43   return 0;
  44 }
  45 /* { dg-final { scan-rtl-dump "Elimination opportunities = 3 realized = 3" "ree" } }  */